Bituminous composition and process of manufacturing the same



, Patented Feb. 19, 1946 :UNITED nrrummous or f waosrl 'coslrrosr'rron'asn rnocnss THE SAME Ir, rltisbm-m'ra, aim-J1" mesne assignments, to Koppel-s company lnc a corporationfoi u No YApplicationDeoem Serial No.48'i,814=

' -in bituminous compositions and processes of preparingthe" same. More particularly the invention relates to the preparation of certain bitumi nous compositions which are greatly improved in regardto viscosity susceptibility to temperature change,,and --which have preferred rheological properties, renderingthem outstandingly. suitable for customary construction purposes and for many new uses, without adversely affecting-their well recognized excellent weather resistant properties.

.Bituminous products have long been used in coating composltions'and in binders. Ingeneral it has, been foundthat most of the various tars and pitches commonly used behave over .the normal range of atmospheric temperatures'as purely viscous liquids, as Judged their shearing stress-rate of shearrelations over wide ranges of shearing stress. The bituminous compositions and the products manufactured by the processes herein described differ from these commonly used tars and pitches in that they have better temperature susceptibilities, that is, less change-in j viscosity with temperature change. and exhibit non-viscous or non-Newtonian flow at atmospheric temperatures, when submitted to shear-- ing-stresses, as well as definite plasticity and little tendency toward embrittlement at relatively low temperatures, while retaining the desirablewater and light resistant properties typical of tar products in general, as demonstrated by extended 'accelerated aging tests and outdoor exposure tests,-

and by accumulated service data and observations made during, actual experience. 7

An object of the present invention is to'provid a bituminous composition of "a highly improvedtype. which in itself has the property of adher-J ing tenaclously to smooth as well'as rough suriaces, and yet after application exhibits less tendency'to flow at relatively high temperatures and little tendency toward embrittlement at reduced temperatures, as contrasted with, comparably specified. grades of similar materials. formerly used, together with theexcellentweather-resistant characteristics mentioned above.-

Another object is t provide a process oi preparing theimproved bituminous composition and particularly aprocess whereby compositions ofcertain desirable characteristics are uniformly obtained. U I

The composition hereinafter described and claimed comprises coal dispersed by controlled digestion in a heat-liqueilable bituminous medium which is composed of, or contains, heavy water gas tar heavy oil, or to which heavy water-gas tar heavy oil is added during or after the digestion and dispersion process, or during or after thermal decomposition of coalinsuch process. In, one procedure, coaiand tar or pitch. are heated to-r .(Cl. 198-44) I gether and, while stirring the mixture, the temperature thereof is gradually increased. over an extended period of time to substantially 300 0., I or preferably to a temperature in the approximate range of 300' C. to-810' 0.- Anydistillate i obtained is discarded. The heated material is fluxed to any required softening point with heavy watergas tar heavy oil to obtain the desired improved bituminous product.

1. 1 ':In-an alternative procedure, coal, and tar or pitch, and heavy water. gas tarheavy oil are initially thoroughly mixed, heated together and while mixing, the temperature is gradually raised v over a-period of time to obtain a product having a desired softening point. In another procedure,

though not as desirable as those indicated above,

- coalis dispersed'in heavy water gas "tar-heavy oil; and tar or pitch are'then added while heating and stirring, During or after aperiod of s gradually increasing temperature, depending.

upon the proportions of materials originally com- .bined, additional quantities oi 'pitch or tar or heavy water gas tar heavy oil, or combinations'of these are added as necessary to obtain a product having any desired softening point over the approximate range of C. to 150' CI and exhib-- iting improved rheological properties. I

The above processes. are varied depending upon the coal and tar or "pitch used and upon the na "ture of the product to be obtained. The coal is a bituminous coal such as, coking coals "including either high or-low volatile bituminous coal,

' and certain commercial non-coking bituminous coals. I i

.Highly-improved results aredei'initely and particularly obtained by usingfor-thetar or pitch constituent heavy watergas tar or a pitch resi.-

due derived from thedistillation of heavy water 7 gas tar. Heavy water gas tar is obtained from water-gas generator plants in" which Bunker-C or similar grades of residual petroleum fuel oil are used for carburetting. This tar. though produced from a petroleumraw material, is composed mostly of. aromatic constituents. Heavy water gastar should be differentiated from what is known as water gas tar, or light water gas tar which is produced in the carburetter of a water gas plant when petroleum distillates are used as carburetting materlals.- In certain industrial groups heavy water gas tar is termen residuum tar todistinguish it from what was formerly known as water gastar or is known today as light water gas tar. Other heat-liqueflable bitumens including tars and pitches, either singly or combinations thereohmay be added to theheavy water gas tar, or may be substituted in wholev or in part for the latter.- Other bitumens in addi-. tion to heavy water gas tar are, for example, coal tar (from high or low temperaturecoking processes) water-gas tar, oil-gas tar. Pintsch gas tar heavy oil so prepared The heavy water gas'tar heavy oil, or high boiling distillate. which is included in the digested coal product,.-or;what is known as coal dispersion pitch, and which lowers the susceptibility of the viscosity of the product to change with temperature, is obtained by dis.- tilling heavy water "gas tar and separating the distillate recoverable above approximately 300' C.

, during the increasing temperature interval when table:

e -e mt we as re s:

, By means of the materials employed, products are prepared of relatively high softening points, having relatively high penetration characteristics at low temperatures, and high yield values when subjected to shearing stress, or in other words increased resistance to flow, at atmospheric temperatures It is found that additional improvement in lowered change of viscosity with and wood tar, and the corresponding pitches derived from the above-mentioned tars.

stantially improved may be demonstrated by observation of recovery after deformation upon removal of thestress causing movement of the improved pitch and by the fact that instead d of obeying the laws of viscous or Newtonian flow, these materials after application and setting-will not flow off of vertical or slanting surfaces at atmospheric temperatures, and deflnitely' exhibit high yield values and non-viscous or non-Newtonian flow .characteristics. These bituminous products remain in place also at I temperatures approaching their softening points when applied in thin films, and they are not brittle at relatively low atmospheric temperatures.

When heating the bituminous plastic product to melt it, or to apply it in a hot liquid state,

the fumes therefrom are found to be less irritating tothe skin or eyes of the workmen than some of the bituminous materials customarily used heretofore, which is of considerable advantage from the standpoint of efficient application. In coating metal, stone, or wooden structures or any smooth surface, no priming coat is usually necessary. The molten product can be applieddirectly to the bare surfaces On such structures as flat or corrugated metal sheets,

- pipes, or wires or articles having rounded surchange of temperature, particularly and dei'initely is thecase in themanufacture of products of the type herein described, which contain heavy water gas tar heavy oil. Though bituminous products made from coal, tar, and oil have heretofore been proposed, the product of the present invention is in many important respects markedly superior. 'I'hat the 'susoepti bility of changein viscosity to change in temperature is considerably improved is amply demonstrated by the softening point determinations and the standard penetration test results at different temperatures for the various examples' of the pitches presented hereinbelow.

As a basis for the empirical evaluation of the .improvement of this property shown by the examples cited, typical softening point and penetration characteristics are given in the table below for a straight distilled coke oven tar pitch, a straight distilled heavy water gas tar pitch, and a coal dispersed pitch prepared from coal, coke oven tan-and coke oven tar heavy oil.

That the rheological properties of products of the type hereinafter described have been Subfaces or sharp corners, little or no peeling takes place as is the case in other coating compositions particularly after weathering.

Sheets or coatings or structural products protected with bituminous products of the present invention withstand the effects of intensive accelerated aging tests. It has been demonstrated that they are highly inert to the action of light (ultra violet and other rays), atmospheric high and low temperatures, relatively sudden atmospheric temperature changes, and water (including rain .water) In outdoor exposure tests over long periods of time and with temperatures ranging as high as over 130 F., no signs of flowing of coatings on metal panels were observed.

These products, though strongly adhesive, do not present a sticky outer surface at atmospheric temperatures. Though they may be rendered hard, they do not fracture easily, and even at low or freezing temperatures they exhibit little tendency toward embrittlement. that coatings of these materials exhibit little or no tendency to chip on or shatter on impact at temperatures as low as freezing temperatures. The products find wide use, therefore, in linings and outer protective coatings of pipes and as a substitute forgalvanizing zinc on steel or iron articles of, various shapes.

Further uses requiring moderate to high melting points are'in binders including battery box,

clay mastic and shingle binders; linings for pipes and tanks; certain coatings for metal surfaces and for saturated felt; bases for roof cements,

column cements, adhesives (such as cut'back' mastic for non-metallic flashings), and as bases for crack fillers or joint fillers and for cold application fluid bituminous cements of various types.

Other uses are in battery box compositions, elec- V trical insulations and seals, extenders for resins as clay mastics. The melting or softening point Drop tests show asset Mi characteristics of the products claimed may be wen a eas and tar' oroil mixtures, and

readily adjusted tomeet the needs of the wide variety of applications by appropriate variation of the relative proportions of, the ingredients and v the method of processing.

I In accomplishing the above purposes, found that in preparation of the products claimed, products with the desired characteristics may be'duplicated by adjustment of the proporstions of coal, dispersing media and heavy water gas tar heavyoil; by control-of heating temperatures; by addition of dispersing media and/or heavy water gas tar heavy oil to a batch under treatment at predetermined stages in the coal digestion process and atpredetermined rates;

I by adjustmentof the length of time 'of mixing and-heatinggiven proportions of the ingredients and of the manner of mixing same; and, if dethefuniform distribution of the heavy water gas tar *heavyoil therein, result in a homogeneous product having a relatively lowerviscosity susceptibility to temperature changes than does the original bitumen.

The penetration tests in each of the examples provided below wereJdetermined according, to

A. 8. T. M. procedure under the following conditions: at 32 F., 200 grams, 60 seconds; at

determined in accordance with the A. S. T. M.

, Ring and Ball methods.

are too low in viscosity for evaluation of flow persionproduct and subsequent addition of heavy water gas tarheavy oil. thereby replacing lower boiling oils by the higher boiling heavy water gas tar heavy oil.

' batch, may be used. The rate of'rise in tempera-.

ture of the heating vessel in the initial stages at. least is preferably low to permit the evaporation of any water present whieh might cause excessive foaming. The coal'used may be preferably initially dehydrated which is best accom-' 'plished by finely dividing it and then subiect-' ing it to a drying treatment. By proper division of the coal to a finely pulverized condition more uniform distribution thereof in the liquid media is readily attained. Coking of the. material or too rapid decomposition of constituents'therein'; particularly where the higher concentrations of coal are employed, is avoided by maintaining moderate rates of temperature rise. The temperature at which, coal and a bituminous medium are heated together to provide the product of the present invention should not apractical standpoint, namely, substantially 270 0., and the temperature shouldnot be permitted to rise so high as to decrease unduly the life properties or improvements thereof by the testsused for the higher melting pitches, it is convenient to use as a numerical index of their viscosity-temperature susceptibilities the mathematical definition I given by the' equation.

obtained byplotting viscosities at two temperatures on A. s. 'r. M. chart n-341-32'r, on which log log viscosities may be easily plotted against be lower than that at which a satisfactory dispersion isobtained within a reasonable time from of the heating equipment, namelmapproximately In adjusting the characteristics of vthe' iinal I product, it is noted that generally theincrease in proportion of coal results in more pronounced departure from' simple viscous flow properties, H

and in increased softening points of the products. The greater the proportion of dispersed coal,ltheharder the final product, and :the,

greater the proportion of admixed heavy water gas tar heavy oil the softer the product and the greater the improvement in temperature susceptibility. The greater the proportion of the coal and heavy water gas tar heavy oil as distinct from tar or pitch, the better the improvements in viscosity-temperature susceptibility and the reater the resistance to flow under stress. The addition of heavy water gas tar heavy oil alone toa bitumen such as coal tar pitch as log absolute temperature.

Forcomparison with such examples, presented below which illustrate more specifically the production of road tars of improved temperature susceptibilitiea'it has been found that many known road tars of the viscosity ranges customarily used have viscosity-temperature susceptibilities of from 1.1 to 1.2, as defined above.

The examples given below'therefore illustrate the definite improvement in lowered temperature of about 305 C. over a period of approximately five and one-half hours. This temperature is maintained for about four hours during which time there results a. distillate of about 5 to 6% based on the tar. At the end of this time heating isdiscontinued and the mixture permitted to cool. 'After about forty minutes and while the temperature, is slowly dropping, about 54 parts by weight of heavy water gas tar heavy oil are-stirred into the heat-treated coal and tar masszs The resulting product is discharged from the still at around 225 C. The softenin poinfof thisproduct is about 102 C., and. the

. penetration at 32 F. is 11; at 77 F. is 20.5; and tit-115 F. is 4c.

Since the normal grades of road tar binders I 800 to 310C. This range isreached in about two and one-half hours and is substantially maintained for about iive hours. The temperature of the charge at the end of another hour is reduced to about 245 C. and about 22 parts by weight of heavy water gas tar heavy oil added while stirring. At two successive intervals thereafter of about thirty minutes apart, about 10 parts by weight -of coke oven pitch are added while stirring. The product is discharged from the still and is ready for use. Its softening point is about 104' C. and the penetration at 32' I. is 15; at 77 1'. is 25; and at 115 F. is 40. 7

Example 3.--A still is charged with about 4770 gallons of heavy water gas tar at about 60" E, about 13,200 pounds of pulverized bituminous coal, and about 1450 gallons heavy water gas tar heavy oil. The charge is then slowly heated to about 300 C. over a period of about twelve hours and is maintained at this temperature for an additional two to four hours. Tests are made on softening point and penetrations and the material is discharged from the still and barreled. A typical sample has a softening point of 112 C. and penetrations at 32' 1". of- 15; at 77' 1". of 22; and at 115 F. of 40. I

' Example 4.--About 69 parts by weight of heavy water gas tar, about 69 parts by weight or coke oven tar and substantally 45 parts by weight of powdered coking coal are brought together and heated slowly to 300 C. over a period of about three to four hours. The temperature is maintained at about 300 C. ioran additional three to four hours whereaiter substantially 73 parts by weight of heavy water gas tar heavy oil are added. After introduction of the oil the heating is discontinued and the resulting product is permitted to cool. The softening point of the product is substantially 103.2 C., and the penetration at 32 1''. is 29; at 77 1''. is 36; and at 115 F. is 60.

Example 5.--About 40 parts by weight of pulverize'd bituminous'coal that has been previously dried, are mixed with about 120 parts by' weight of heavy water gas tar. The mixture is heated and the temperature gradually brought up to about 300 C. over a period of three to four hours. This temperature is maintained for an additional four hours when heating is discontinued and about one hour later about 62 parts by weight of heavy water gas tar heavy oil'are added. The resulting material is allowed to cool andis discharged from the still in liquid form. The product has a softening point of about 104.5 0.,

and penetrations at 32 F. of 18; at 77 F. of 28;

penetrations at 32 F. of 21;

asaaoar tar and 15 parts by weight'of powdered bituminous coal are brought together and heated over a period of about three hours to a temperature of about 305, C. Theheating is continued at about this temperature for an additional six hours. At the end of this period about 14% by weight of heavy water gas tarheavy oil based on the weight of the heated material isadded, distributed therein, and the heating is discontinued. The product has a softening'polnt of about 74 0.; and penetrations at 32' l". of 12; at 77 F. of 27; and at 115 F. of 72.

By way of comparison, a product prepared from substantially the same proportions of coke oven tan. powdered bituminous coal and coke oven tar heavy oil and under substantially similar conditions as in Example 7, is a product having a sottening'point of about 74 C., and penetrations at 32 F. of 3.5; at 77 F. of 14.0; at 115 F. of 63.0. Thusthe latter product is considerably more susceptible to changes in temperature than the product of Example 7 in which heavy water gas tarheavy oil is substituted for coke oven tar heavy oil. Example 8 also illustrates the improvement effected by use of heavy water gas tar heavy oil in a coal dispersion coke oven tar pitch.

Example 8.--A mixture prepared from approximately 174 parts by weight of coke oven tar and approximately 58 parts by weight of pulverized bituminous coal is heated to about 300 C. over a period of seven to eight hours. The heating is discontinued and about 72 parts by weight of heavy water gas tar heavyoil are added whereupon the heating is resumed at about 300 C. for an additional one to two hours. Then another 15parts by weightof heavy water gas tar heavy oil are added whereaiter the heating is discontinued and after thorough mixing the product is permitted to cool. The soiteningpoint of the product is about 89 C. and the penetra- 1 tion at 32F. is 24; at 77 F. is 38; and at 115 F. is 67. H

Example 9.-Approximately 31 parts by weight of pulverized bituminous coal and about 125 parts by weight of heavy water gas tar are heated together to a temperature in the range of approximately 300 to 310 C. withina period of four to live hours. is continued for an additional four hours. Then the heating is discontinued for about forty-five minutes whereupon approximately 48 parts by weight of heavy watergas tar heavy oil are thoroughly mixed into the heated mixture. The product is permitted to cool and is found to have a softening point of about 833 C., and at 77 F. of .40; and at 115 F. of 95. v

Example 10.- parts by weight of heavy water gas tar and 15 parts by weight of powdered bituminous coal are heated together to a temperature of about 300 C. over a period of two to mixture is maintained within the range of about 300 to 310 C. During the heating about 9% of the material based on the tar is distilled 017, and rejected. The heating is discontinued and after about forty minutes 80 parts by weight oiheavy water gas tar heavy oil are thoroughly stirred in and uniformly distributed in the mixture. The resulting productv is permitted to cool. The produc'thas a softening point of about 111.5 0.,

and penetrations at 32 F. of 31; at 77 F. of 46;

and at 115 l3. of 80.

I Example 7.-60 parts by weight of coke oven three hours. For an additional three hours the temperature of the mixture is maintained at about 300 C. The mixture is permitted to cool to around 250 C. and air is introduced and thoroughly distributed in the mixture for about one hour. The introduction of the air is then stopped to prevent too great an increase in temperature. Aiter suflicient cooling the introduction of air is resumed and continued for about thirty -tlve minutes. During this time the temperature is held as near as possible at about 250 C. After the introduction of air which raises the softening point of the heated material from C. to about The heating in this range or as; and'at 115 F. or '19.

ter gas tar and parts '01 ;,pulveriz e'd con-s:

- 300 c.; aintainedetsoo-m 310C. rarer: ad

tional four hours, removing approxirnatelyll I,

by weight (on the basisot the tar present). of.-

0., about 32% by weight (based on the heated material) of heavy water gas tar heavy oilis and the heating continued for about one 'The resulting product has a softening of about 855C and penetrations at 32 11.-A mixture or approximately 59 by weight or heavy fwater'gas tar, 1 to 2 31 powdered bituminous coal is heated to about o with the heated material, .'Ihe, mixture is per; mitted to cool. The'product has aisoftening porn of about 112.5 CL, and penetrationsiat" 32 FL o 3%; at 17 Roi 52; and at 115 F. of 104;

Example 12.-A mixture or about 15 'partsbii weight of powdered bituminouscoal; 58 partsby weight of coke'oven tar and 1 to 2 parts by weight of sulfur-is heated to a temperature in the-range or 300 tof310 C. over a period of about three hours. The temperature is held within this range for an additional four to five hours; 'At the end 1 01 the latter-period about 22 palrtsby weight. or heavy water gas tar. lheavy oil' are added the dlinm The producthasasoite 81.5 C., and penetrations at 32'.

Example 13.':80 parts ofheavy as mixed slowly heated tour-hours distillate which is'rejected'. Vacuumis then applied tothesystem which effects the removal or about 7% additional distillate from the tar, producing a pitch residue'having a softening point v of 137 C. Incorporation of 36% of heavy water gas tar heavy oil (on the basis or the remaining combined heated materials) produces a bitumen penetrations 0138.6 atlajz rln ts earl? F. ;,and 130 v then introduced, th mix lojved to cool. h equivalentfto that-10f a ma c. At 35. C; the viseo'sit'yor this road binder; is

77,500 centistokeawhile at 50" C. its viscosity is 10,100 centistokes, from which a visco'sity-temperature susceptibility of 0.93 may be calculated.

Example 1-5.200 parts by weight of coke oven coal tar and 2 0 of pulverized coal are inti mately mixed and slowly heated during four hours toa temperature of 300 C and main tained at 300 C.'Ior five hours, after which 43 parts of heavy water gas tax heavy oil are added, and the mixture allowed to cool while bein stirred. This product equivalent to a road tar of RT-lo'grade, is found to have a viscosity of 234,-a00 centistokes at C., and a viscosity of $7,230 eentistokes at C., from which a vishy weight otsuliur, and 16 parts b'y weight s m 0 .s i t 01.26; atTP F.

a a V earth-fratgrat i "is round tohavea sottening point e r about 26 6b heavy water gas tax obtained in carburetting a {gas with residualipetroleum fuel oil in a 'water;

' gas generator plant the said coal-digestion pitch I at 7'? F. of 27.0; and at F, 01363.0.

10 1 over a period of about four hours. vThe at this temperature is continued 101' an nal three hours.- After another one or two hours about 34 parts by weight of heavy water gas tar heavy oil arethoroughlymixed funiforrn dispersion .01" said 'digested'coal in said bitumen and said heavy water gas tar heavy oilgf I 3. In a bituminous product, a plastic composition consisting of coal-digestion pitch containing. heavy water gas tar heavy oilderived from heavy. water gas tar obtainedin carburetting ag'aswith residual petroleum fuel oil in awater-gas .generw havinga softening ,PDint of about 83. C., f

some:

. 1. In a bituminous product, a plastic composition consistin'g of coal-digestion pitch containing heavy water gas tar-heavy oil derived from heavy water gas tarobtained in carburetting a gas with residual. petroleum. fuel oil in a water-gas gen erator'plant, the said heavy water gas tar heavy oil having a. distillation range. between about 270 (Land about 400C.

tion. consisting of 'coabdlgestion pitch containing heavy water gas tar heavy oil derived from heavy ter gas-"tar obtained in carburettlng a gas it residual-petroleum Iuel o'il'i'n a water-gas llant ythe said coal-digestion pitch rein-jaf mperature range or substantially 300 tov 310?:C.--.in a heat-lique'flablebitumen-and from ator plant, thesaid coal-digestion pitch resulting .iroin :therinaifiigestion or bltuminouscoal insteirip'e'arature'-range of substantially 3009!;0-310" tar' 'and irom-uniiorm dispersion oflsaid coal 'in'saidtar ands'aid heavy water "gas tar heavy oil.

"4. In ai bituminous product, a plastic composition; consistlrifd'l; coal-digestion pitchcontain heavy; oil. derived from f.

ing .rheavy were tained h we coal in a temperature range of substantially 300 to 310 Qin'heavy water gas tar and from uniform dispersion of said digested coal in said heavy water gas tar and said heavy water gas tar heavy oi a I 5. .In a bituminous product, a plastic composition consisting of coal-digestion pitch containing heavyyvater gas heavy oil derivedirornheaw water 'gastar obtained carburetting a gas with :re'sidualpetroleum fuel oil in a water-gas mrI-hla 'ih? s d e d ti u vh resul n from thermal digestion' or bituminousfcdal in. a-

.in tree. flvqateiiftargas pitch and from-uniform er gas' tar'pltch and said heavy watergas' ta 'tio'n consisting of V al digestionpitch' containheavy water gasrtar heavy oil derived .from

resulting irom.-thermal digestion of bituminous coal in a temperature range of substantially 300 to 310 C. in coal tar and from uniform dispersion of said digested coal in said coal tar heavy water gas tar heavy oil. 7

7. In a bituminous product. a plastic composb 2 In a bituminous product, a plastic composibmemrmsi. digestion of bituminous coal temperature range .of substantially 300,gto 310 p don/6r said digested coal in; said. heavy J.

. Ina bitumm iis rennet, stasis-amps;

and said' witha melting point in the range of 35 C. to

C. having rel my high penetration at low st mospheric scrotum, 32 F as well as rele tivelc; low pct .trotion at high atmospheric tern persture, 115- 5t, and having a, relatively high sofiternng point with the said penetrations at 32 end at 115 F.

3. Lin o bituminous product, a. plastic composite tic-n consisting coohdigestion pitch containing heavy water gas tor heavy oil derived from heavy water gas tar obtained in corburetting a gas with residual petroleum fuel oil in a water gas genorator plant, the said coal-digestion pitch with melting point in. the range of 35 C. to 150 C. hevuig relatively high penetration at low atmospheric temperature, 32 751, as well as relatively low penetration at high atmospheric temperature, 115 F., and having a, relatively high softening point with the said penetrations at 32 F, and at 115 T52, and exhibiting no flow from vertical surfaces at atmospheric temperatures above 130 It 52', In a. bituminous product, a, plastic compositlon consisting of coal-digestion pitch contciningf'heavy water gas tar heavy oil derived. from heavy water gas tar obtained in carburetting a. gas with residual petroleum fuel oil in a water- I 7 gas generator plant, the said heavy Water gas tar heavy oil being a. distillate from said heavy water tor recoverable above approximately 300 0., end sold cool-digestion pitch with a melting at in the range of 35 9. to 150 C. having relatively high penetration at low atmospheric temperature, l t, relatively low penetroticn ct atmospheric temperature, 115 F., and having at relatively high softening point with the said penetrations at 32 F, and at 115 F.

10, In a bituminous product, a, plastic composition consisting of cosl-digestion pitch resultin from thermal digestion of bituminous coal in a temperature range of substantisily 270 C. tour)- prmdrncteiy 350 C in c heat=liquefiable bitumen end from uniform dispersion of said dlgestedcoal in said bittunen and heavy water gas tar heavy oil derived from heavy water gas tor obtained in carburctttng agas with residual petroleum Iuel oil in c, s ster-gas generator plant.

11. In s. bituminous product, a plastic composition consisting of coal-digestion pitch. resultirom therrnsl digestion bituminous coal in o temperature range of substantially 370 C. to

approximately 350 ll.- in s, heet-liquefiabl'e bitu men and from tunform dispersion or said digested coal in said bitumen. and heavy water gas tar heelvy oil derived from heavy water gets tar obtained. in ccrburetting a gas with residual petroleznu fuel oil in u water-gas generator plant, the said cosl-digesticn pitch with a melting point 111 the range or 35 ii. to 150 (3. having relatively high penetration at low atmospheric temperature,

'" as relatively low penetration at on, as nigh atmospheric temperature, 115 R, and having a. relatively high softening point with the said penetrations at 32 F. and at 115 F.

13%. in s, bituminous product, a, plastic compo sitlon consisting of coal-digestion pitch contuirv inc heavy water gas tar heavy oil derived from heavy water gas tar obtained in carburettlng at gas with residual petroleum fuel oil in o, watergas generator plant, the said heavy water gas tor heavy oil being a. distillate from said heavy water gas tor recovereble above approximately s c" and the said coal-digestion pitch resulting it thermal digestion of bituminous cool in e temperature range ofsubstontially 300 to 310 in tor from uniform. dispersion of said digested coal in said tar and said heavy water gets tor heavy oil.

13. bituminous product, a, plastic composition consisting of coal-digestion pitch containing heavy water gas tar heavy oil derived from heavy water gas tar obtained in carburetting a gas with residual petroleum fuel oil in a, watergas generator plant, the said heavy water gas tor heavy 011 being a distillate from said heavy water gas tar recoverable above approximately 300 C., the said coal-digestion pitch resulting from thermal digestion of bituminous coal in a temperature range of substantially 300 to 310 C. in tor and from uniform dispersion of said digested coal in said tar and said heavy water gas tar heavy oil, the said coal-digestion pitch with a, meltingpoint in the range of 35 C. to 150 C. having relatively high penetration at low atmospheric temperature, 32 FL, as well as relatively low penetration at high atmospheric temperature, 115 F., and having a. relatively high softening point with the said penetrations at 32 F. and at 115 F., and exhibiting no flow from vertical surfaces at atmospheric temperatures above 14, In a. bituminous product, a. plastic composition consisting of coal-digestion pitch resulting from thermal digestion of bituminous coal in a temperature range of substantially 270 C. to approximately 350 C. in a heat-liqueflable bitumen and'from uniform dispersion in said bitumen and heavy water gas tar heavy oil derived from heavy water gas tar obtained in carburetting gas with residual petroleumfuel oil in a. water-gas generator plant, the said composition having a. viscosity-temperature susceptibility of below 1.1 calculated from the expression s s; s=0.221 1 Log 1 wherein U1 and U: are the kinematic viscosities in centistokes at the absolute temperatures T1 and T2 respectively.

15. II. a method of preparing a coal-digestion pitch product, the steps of first thermally digesting bituminous coal in a heat-liquefiable bitumen in a. temperature range 01 about 270 C. to approximately 350 C. and then stirring into the resulting digested coal mass heavy water gas tar heavy oil derived from heavy water EELS tar obtained in carburettlns a gas with residual petroleum fuel oil in a. water-gas generator plant.

16. In a method of preparing a coal-digestion pitch product, the steps of first thermally digest- :lng bituminous coal in a heat-'llquefieble bitumen in a. temperature range of about 270 C. to approximately 350 C. and in the presence of a dehydrogeneting agent selected from the group consisting of sulfur and oxygen, and then stirring into the resulting digested coal mass heavy water gas tar heavy oil derived from heavy water gas tar obtained in cerburetting a gas with residual petroleum fuel. oil in e wetengas generator plant.

F0 FAIR, JR. 

